The use of syngas from coal and biomass gasification is of increasing interest with regard to the demands of advanced energy generation and the production of alternative fuels. Due to the interest in distributed power generation and liquid fuels production, smaller compact gasification units are desired, including compact, yet simple, robust, and effective syngas cleanup. The compact, simple, and robust feature is as important as the effectiveness for distributed-generation systems. Without these characteristics, distributed generation systems are too costly to build and operate for the amount of electricity or liquid fuel produced. In addition however, the syngas must be free of contaminants, for example, metals, sulfur, ammonia, tars, alkalis, particulate matter, and the like in order to eliminate fouling and poisoning of sensitive downstream components such as gas turbine blades, fuel cells, gas separation membranes, and syngas reforming catalysts, such as water-gas shift (wgs) catalysts or Fischer-Tropsch (FT) catalysts.
As such, there is a need for compact, effective processes for treating syngas to reduce the levels of tars, metals, ammonia, halides, particulates and sulfur contaminants.